for Japanese


1 February, 2019

JAEA Achieves 150 Hours of Continuous Hydrogen Production Toward Utilization of Heat from HTGRs

On January 25, the Japan Atomic Energy Agency (JAEA) announced that it had succeeded in producing hydrogen continuously for 150 hours using a thermal-chemical iodine-sulfur (IS) process that JAEA developed to more efficiently utilize the heat supply capabilities of high-temperature gas-cooled reactors (HTGRs).  

JAIF President Takahashi visited HTTR reactor building (April 2018)

The thermochemical IS process combines three reactions using iodine (I) and sulfur (S) – sulfate degradation, a Bunsen reaction, and hydrogen iodide decomposition. It produces hydrogen by splitting water (an abundant resource) into H2 and O2 using heat generated without CO2 emissions. Moreover, the iodine and sulfur are circulated within the system, emitting no waste to the outside environment.

At the same time, given that extremely corrosive liquids such as sulfuric acid are used at high temperatures, for commercial use, it was necessary to develop technology for manufacturing equipment/facilities to identify materials suitable for different conditions and to validate their reliability. JAEA successfully developed durable reactor vessels for each reaction process.

Three years ago, in 2016, JAEA succeeded in in test-producing hydrogen, making about ten liters per hour for eight hours. After further development of elemental technology toward more stable production of hydrogen, JAEA has now succeeded in continuous production of hydrogen for 150 hours (at about 30 liters/hour), a milestone in long-duration operation.

[clizk to zoom] Mechanism of IS processes (quoted from materials released by the Ministry of Education, Culture, Sports, Science and Technology (MEXT))







JAEA will continue to accumulate operational data and carry out R&D toward practical use of the system to produce large amounts of hydrogen in a stable manner, including automatic operations control. It aims next at a demonstration of hydrogen production using the High-Temperature Engineering Test Reactor (HTTR). HTTR is now ALSO undergoing a safety compatibility examination under the new regulatory standards by the Nuclear Regulation Authority (NRA).





This site uses Akismet to reduce spam. Learn how your comment data is processed.

SNS facebooktwitter

NPPs Map


“The current situation at Fukushima Daiichi NPS” -From 3.11 toward the future- (ver, Jan. 2020)

23 January, 2020
“The current situation at Fukushima Daiichi NPS” -From 3.11 toward the future- (ver, Jan. 2020)07:47

Recent News

30 June, 2020
“Existing NPPs to Enter Age of 80-Year Operations” JAIF Annual Survey Says
16 June, 2020
Toshiba ESS and Yokohama National University Boost Joint Research to Upgrade Heavy-Ion Cancer Therapy, Using Kanagawa Prefectural Facility
8 June, 2020
NRA Grants Permission to Make Changes to Reactor Installation at HTTR under New Regulatory Standards
22 May, 2020
Sendai-2 Starts Periodic Inspection, with Due Date Imminent to Install Specific Safety Facilities
15 May, 2020
NRA Issues Draft Review Report for Rokkasho Reprocessing Plant
30 April, 2020
Construction Begins of Next Generation Synchrotron Radiation Facility at Tohoku University, to Be Used for Fuel Cells and Pharmaceuticals
27 April, 2020
Superconducting-Coil Tokamak Plasma Test Device (JT-60SA) Installed at Naka Fusion Institute, with Plasma Generation to Begin in Autumn
17 April, 2020
Japan’s CO2 Emissions Fall 4.6% in FY18, Thanks in Part to Restart of NPPs
14 April, 2020
ANRE Begins Hearing from Concerned Parties on Handling of Treated Contaminated Water at Fukushima Daiichi NPPs
14 April, 2020
IAEA Issues Report Reviewing Treated Contaminated Water at Fukushima Daiichi NPPs, Praising Earlier ANRE Report